Hi, I have the same problem, and worked out that it was too small to see, but when I go into the relevant screen to fix it, I can't make the dimensions text more than 5mm. It won't let me type in any other number than what appears in the dropdown.

I am drawing a car chassis in real world dimensions (3000mm * 1500mm approx) and when I print the diagram on A4 I can't read the dimensions.